vasotocin

biochemistry

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Last updated

July 14, 2026

Quick Summary

Vasotocin is a polypeptide hormone found in most vertebrates below mammals. It is similar in function to oxytocin and vasopressin. These hormones are produced in the hypothalamus and released from the neurohypophysis, a part of the pituitary gland.12

While vasotocin is present in lower vertebrates, mammals primarily utilize oxytocin and vasopressin. These hormones play crucial roles in regulating water balance, blood pressure, and smooth muscle contractions, such as those in the uterus and mammary glands. The evolutionary history of these hormones suggests they originated from a common precursor, with vasotocin being one of the earliest forms.2

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endocrine system
The hypothalamic-pituitary-target organ axis
The second peptide is arginine vasotocin, which is found in all nonmammalian vertebrates as well as in fetal mammals. Chemically, vasotocin is a hybrid of oxytocin and vasopressin, and it appears to have the biologic properties of both oxytocin (which stimulates contraction of muscles of the reproductive tract, thus playing…
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The second peptide is arginine vasotocin, which is found in all nonmammalian vertebrates as well as in fetal mammals. Chemically, vasotocin is a hybrid of oxytocin and vasopressin, and it appears to have the biologic properties of both oxytocin (which stimulates contraction of muscles of the reproductive tract, thus playing…
Read More